#!/bin/bash
# Tetris Game
# 10.21.2003 xhchen<[email]xhchen@winbond.com.tw[/email]>
#APP declaration
APP_NAME="${0##*[\\/]}"
APP_VERSION="1.0"
#颜色定义
cRed=1
cGreen=2
cYellow=3
cBlue=4
cFuchsia=5
cCyan=6
    cWhite=7
colorTable=($cRed $cGreen $cYellow $cBlue $cFuchsia $cCyan $cWhite)

#位置和大小
    iLeft=3
    iTop=2
    ((iTrayLeft = iLeft + 2))
    ((iTrayTop = iTop + 1))
    ((iTrayWidth = 10))
((iTrayHeight = 15))

#颜色设置
    cBorder=$cGreen
    cScore=$cFuchsia
    cScoreValue=$cCyan

#控制信号
#改游戏使用两个进程，一个用于接收输入，一个用于游戏流程和显示界面;
#当前者接收到上下左右等按键时，通过向后者发送signal的方式通知后者。
    sigRotate=25
    sigLeft=26
    sigRight=27
    sigDown=28
    sigAllDown=29
    sigExit=30

#七中不同的方块的定义
#通过旋转，每种方块的显示的样式可能有几种
    box0=(0 0 0 1 1 0 1 1)
    box1=(0 2 1 2 2 2 3 2 1 0 1 1 1 2 1 3)
    box2=(0 0 0 1 1 1 1 2 0 1 1 0 1 1 2 0)
    box3=(0 1 0 2 1 0 1 1 0 0 1 0 1 1 2 1)
    box4=(0 1 0 2 1 1 2 1 1 0 1 1 1 2 2 2 0 1 1 1 2 0 2 1 0 0 1 0 1 1 1 2)
    box5=(0 1 1 1 2 1 2 2 1 0 1 1 1 2 2 0 0 0 0 1 1 1 2 1 0 2 1 0 1 1 1 2)
box6=(0 1 1 1 1 2 2 1 1 0 1 1 1 2 2 1 0 1 1 0 1 1 2 1 0 1 1 0 1 1 1 2)
#所有其中方块的定义都放到box变量中
box=(${box0[@]} ${box1[@]} ${box2[@]} ${box3[@]} ${box4[@]} ${box5[@]} ${box6[@]})
#各种方块旋转后可能的样式数目
countBox=(1 2 2 2 4 4 4)
#各种方块再box数组中的偏移
offsetBox=(0 1 3 5 7 11 15)

#每提高一个速度级需要积累的分数
    iScoreEachLevel=50        #be greater than 7

#运行时数据
    sig=0                #接收到的signal
    iScore=0        #总分
    iLevel=0        #速度级
    boxNew=()        #新下落的方块的位置定义
    cBoxNew=0        #新下落的方块的颜色
    iBoxNewType=0        #新下落的方块的种类
    iBoxNewRotate=0        #新下落的方块的旋转角度
    boxCur=()        #当前方块的位置定义
    cBoxCur=0        #当前方块的颜色
    iBoxCurType=0        #当前方块的种类
    iBoxCurRotate=0        #当前方块的旋转角度
    boxCurX=-1        #当前方块的x坐标位置
    boxCurY=-1        #当前方块的y坐标位置
    iMap=()                #背景方块图表

#初始化所有背景方块为-1, 表示没有方块
    for ((i = 0; i < iTrayHeight * iTrayWidth; i++)); do iMap[$i]=-1; done


#接收输入的进程的主函数
function RunAsKeyReceiver()
{
    local pidDisplayer key aKey sig cESC sTTY

	pidDisplayer=$1
	aKey=(0 0 0)

	cESC=`echo -ne "\033"`
	cSpace=`echo -ne "\040"`

#保存终端属性。在read -s读取终端键时，终端的属性会被暂时改变。
#如果在read -s时程序被不幸杀掉，可能会导致终端混乱，
#需要在程序退出时恢复终端属性。
	sTTY=`stty -g`

#捕捉退出信号
	trap "MyExit;" INT TERM
	trap "MyExitNoSub;" $sigExit

#隐藏光标
	echo -ne "\033[?25l"


	while :
	    do
#读取输入。注-s不回显，-n读到一个字符立即返回
		read -s -n 1 key

		    aKey[0]=${aKey[1]}
	    aKey[1]=${aKey[2]}
	    aKey[2]=$key
		sig=0

#判断输入了何种键
		if [[ $key == $cESC && ${aKey[1]} == $cESC ]]
		    then
#ESC键
			MyExit
			elif [[ ${aKey[0]} == $cESC && ${aKey[1]} == "[" ]]
			then
			if [[ $key == "A" ]]; then sig=$sigRotate        #<向上键>
			    elif [[ $key == "B" ]]; then sig=$sigDown        #<向下键>
				elif [[ $key == "D" ]]; then sig=$sigLeft        #<向左键>
				elif [[ $key == "C" ]]; then sig=$sigRight        #<向右键>
				fi
				elif [[ $key == "W" || $key == "w" ]]; then sig=$sigRotate        #W, w
				elif [[ $key == "S" || $key == "s" ]]; then sig=$sigDown        #S, s
				elif [[ $key == "A" || $key == "a" ]]; then sig=$sigLeft        #A, a
				elif [[ $key == "D" || $key == "d" ]]; then sig=$sigRight        #D, d
				elif [[ "[$key]" == "[]" ]]; then sig=$sigAllDown        #空格键
				elif [[ $key == "Q" || $key == "q" ]]                        #Q, q
				then
				MyExit
				fi

				if [[ $sig != 0 ]]
				    then
#向另一进程发送消息
					kill -$sig $pidDisplayer
					fi
					done
}

#退出前的恢复
function MyExitNoSub()
{
    local y

#恢复终端属性
	stty $sTTY
	((y = iTop + iTrayHeight + 4))

#显示光标
	echo -e "\033[?25h\033[${y};0H"
	exit
}


function MyExit()
{
#通知显示进程需要退出
    kill -$sigExit $pidDisplayer

	MyExitNoSub
}


#处理显示和游戏流程的主函数
function RunAsDisplayer()
{
    local sigThis
	InitDraw

#挂载各种信号的处理函数
	trap "sig=$sigRotate;" $sigRotate
	trap "sig=$sigLeft;" $sigLeft
	trap "sig=$sigRight;" $sigRight
	trap "sig=$sigDown;" $sigDown
	trap "sig=$sigAllDown;" $sigAllDown
	trap "ShowExit;" $sigExit

	while :
	    do
#根据当前的速度级iLevel不同，设定相应的循环的次数
		for ((i = 0; i < 21 - iLevel; i++))
		    do
			sleep 0.02
			    sigThis=$sig
			    sig=0

#根据sig变量判断是否接受到相应的信号
			    if ((sigThis == sigRotate)); then BoxRotate;        #旋转
				elif ((sigThis == sigLeft)); then BoxLeft;        #左移一列
				    elif ((sigThis == sigRight)); then BoxRight;        #右移一列
				    elif ((sigThis == sigDown)); then BoxDown;        #下落一行
				    elif ((sigThis == sigAllDown)); then BoxAllDown;        #下落到底
				    fi
				    done
#kill -$sigDown $$
				    BoxDown        #下落一行
				    done
}


#BoxMove(y, x), 测试是否可以把移动中的方块移到(x, y)的位置, 返回0则可以, 1不可以
function BoxMove()
{
    local j i x y xTest yTest
	yTest=$1
	xTest=$2
	for ((j = 0; j < 8; j += 2))
	    do
		((i = j + 1))
		    ((y = ${boxCur[$j]} + yTest))
		    ((x = ${boxCur[$i]} + xTest))
		    if (( y < 0 || y >= iTrayHeight || x < 0 || x >= iTrayWidth))
			then
#撞到墙壁了
			    return 1
			    fi
			    if ((${iMap[y * iTrayWidth + x]} != -1 ))
				then
#撞到其他已经存在的方块了
				    return 1
				    fi
				    done
				    return 0;
}


#将当前移动中的方块放到背景方块中去,
#并计算新的分数和速度级。(即一次方块落到底部)
function Box2Map()
{
    local j i x y xp yp line

#将当前移动中的方块放到背景方块中去
	for ((j = 0; j < 8; j += 2))
	    do
		((i = j + 1))
		    ((y = ${boxCur[$j]} + boxCurY))
		    ((x = ${boxCur[$i]} + boxCurX))
		    ((i = y * iTrayWidth + x))
		    iMap[$i]=$cBoxCur
		    done

#消去可被消去的行
		    line=0
		    for ((j = 0; j < iTrayWidth * iTrayHeight; j += iTrayWidth))
			do
			    for ((i = j + iTrayWidth - 1; i >= j; i--))
				do
				    if ((${iMap[$i]} == -1)); then break; fi
					done
					    if ((i >= j)); then continue; fi

						((line++))
						    for ((i = j - 1; i >= 0; i--))
							do
							    ((x = i + iTrayWidth))
								iMap[$x]=${iMap[$i]}
							done
							    for ((i = 0; i < iTrayWidth; i++))
								do
								    iMap[$i]=-1
									done
									done

									if ((line == 0)); then return; fi

#根据消去的行数line计算分数和速度级
									    ((x = iLeft + iTrayWidth * 2 + 7))
										((y = iTop + 11))
										((iScore += line * 2 - 1))
#显示新的分数
										echo -ne "\033[1m\033[3${cScoreValue}m\033[${y};${x}H${iScore}         "
										if ((iScore % iScoreEachLevel < line * 2 - 1))
										    then
											if ((iLevel < 20))
											    then
												((iLevel++))
												((y = iTop + 14))
#显示新的速度级
												echo -ne "\033[3${cScoreValue}m\033[${y};${x}H${iLevel}        "
												fi
												fi
												echo -ne "\033[0m"


#重新显示背景方块
												for ((y = 0; y < iTrayHeight; y++))
												    do
													((yp = y + iTrayTop + 1))
													    ((xp = iTrayLeft + 1))
													    ((i = y * iTrayWidth))
													    echo -ne "\033[${yp};${xp}H"
													    for ((x = 0; x < iTrayWidth; x++))
														do
														    ((j = i + x))
															if ((${iMap[$j]} == -1))
															    then
																echo -ne "  "
															else
															    echo -ne "\033[1m\033[7m\033[3${iMap[$j]}m\033[4${iMap[$j]}m[]\033[0m"
																fi
																done
																done
}


#下落一行
function BoxDown()
{
    local y s
	((y = boxCurY + 1))        #新的y坐标
	if BoxMove $y $boxCurX        #测试是否可以下落一行
	    then
		s="`DrawCurBox 0`"        #将旧的方块抹去
		((boxCurY = y))
		s="$s`DrawCurBox 1`"        #显示新的下落后方块
		echo -ne $s
	else
#走到这儿, 如果不能下落了
	    Box2Map                #将当前移动中的方块贴到背景方块中
		RandomBox        #产生新的方块
		fi
}

#左移一列
function BoxLeft()
{
    local x s
	((x = boxCurX - 1))
	if BoxMove $boxCurY $x
	    then
		s=`DrawCurBox 0`
		((boxCurX = x))
		s=$s`DrawCurBox 1`
		echo -ne $s
		fi
}

#右移一列
function BoxRight()
{
    local x s
	((x = boxCurX + 1))
	if BoxMove $boxCurY $x
	    then
		s=`DrawCurBox 0`
		((boxCurX = x))
		s=$s`DrawCurBox 1`
		echo -ne $s
		fi
}


#下落到底
function BoxAllDown()
{
    local k j i x y iDown s
	iDown=$iTrayHeight

#计算一共需要下落多少行
	for ((j = 0; j < 8; j += 2))
	    do
		((i = j + 1))
		    ((y = ${boxCur[$j]} + boxCurY))
		    ((x = ${boxCur[$i]} + boxCurX))
		    for ((k = y + 1; k < iTrayHeight; k++))
			do
			    ((i = k * iTrayWidth + x))
				if (( ${iMap[$i]} != -1)); then break; fi
				    done
					((k -= y + 1))
					if (( $iDown > $k )); then iDown=$k; fi
					    done

						s=`DrawCurBox 0`        #将旧的方块抹去
						((boxCurY += iDown))
						s=$s`DrawCurBox 1`        #显示新的下落后的方块
						echo -ne $s
						Box2Map                #将当前移动中的方块贴到背景方块中
						RandomBox        #产生新的方块
}


#旋转方块
function BoxRotate()
{
    local iCount iTestRotate boxTest j i s
	iCount=${countBox[$iBoxCurType]}        #当前的方块经旋转可以产生的样式的数目

#计算旋转后的新的样式
	((iTestRotate = iBoxCurRotate + 1))
	if ((iTestRotate >= iCount))
	    then
		((iTestRotate = 0))
		fi

#更新到新的样式, 保存老的样式(但不显示)
		for ((j = 0, i = (${offsetBox[$iBoxCurType]} + $iTestRotate) * 8; j < 8; j++, i++))
		    do
			boxTest[$j]=${boxCur[$j]}
		    boxCur[$j]=${box[$i]}
		    done

			if BoxMove $boxCurY $boxCurX        #测试旋转后是否有空间放的下
			    then
#抹去旧的方块
				for ((j = 0; j < 8; j++))
				    do
					boxCur[$j]=${boxTest[$j]}
				    done
					s=`DrawCurBox 0`

#画上新的方块
					for ((j = 0, i = (${offsetBox[$iBoxCurType]} + $iTestRotate) * 8; j < 8; j++, i++))
					    do
						boxCur[$j]=${box[$i]}
					    done
						s=$s`DrawCurBox 1`
						echo -ne $s
						iBoxCurRotate=$iTestRotate
			else
#不能旋转，还是继续使用老的样式
			    for ((j = 0; j < 8; j++))
				do
				    boxCur[$j]=${boxTest[$j]}
				done
				    fi
}


#DrawCurBox(bDraw), 绘制当前移动中的方块, bDraw为1, 画上, bDraw为0, 抹去方块。
function DrawCurBox()
{
    local i j t bDraw sBox s
	bDraw=$1

	s=""
	if (( bDraw == 0 ))
	    then
		sBox="\040\040"
	else
	    sBox="[]"
		s=$s"\033[1m\033[7m\033[3${cBoxCur}m\033[4${cBoxCur}m"
		fi

		for ((j = 0; j < 8; j += 2))
		    do
			((i = iTrayTop + 1 + ${boxCur[$j]} + boxCurY))
			    ((t = iTrayLeft + 1 + 2 * (boxCurX + ${boxCur[$j + 1]})))
#\033[y;xH, 光标到(x, y)处
			    s=$s"\033[${i};${t}H${sBox}"
			    done
			    s=$s"\033[0m"
			    echo -n $s
}


#更新新的方块
function RandomBox()
{
    local i j t

#更新当前移动的方块
	iBoxCurType=${iBoxNewType}
    iBoxCurRotate=${iBoxNewRotate}
    cBoxCur=${cBoxNew}
    for ((j = 0; j < ${#boxNew[@]}; j++))
	do
	    boxCur[$j]=${boxNew[$j]}
	done


#显示当前移动的方块
	    if (( ${#boxCur[@]} == 8 ))
		then
#计算当前方块该从顶端哪一行"冒"出来
		    for ((j = 0, t = 4; j < 8; j += 2))
			do
			    if ((${boxCur[$j]} < t)); then t=${boxCur[$j]}; fi
				done
				    ((boxCurY = -t))
				    for ((j = 1, i = -4, t = 20; j < 8; j += 2))
					do
					    if ((${boxCur[$j]} > i)); then i=${boxCur[$j]}; fi
						if ((${boxCur[$j]} < t)); then t=${boxCur[$j]}; fi
						    done
							((boxCurX = (iTrayWidth - 1 - i - t) / 2))

#显示当前移动的方块
							echo -ne `DrawCurBox 1`

#如果方块一出来就没处放，Game over!
							if ! BoxMove $boxCurY $boxCurX
							    then
								kill -$sigExit ${PPID}
					ShowExit
					    fi
					    fi



#清除右边预显示的方块
					    for ((j = 0; j < 4; j++))
						do
						    ((i = iTop + 1 + j))
							((t = iLeft + 2 * iTrayWidth + 7))
							echo -ne "\033[${i};${t}H        "
							done

#随机产生新的方块
							((iBoxNewType = RANDOM % ${#offsetBox[@]}))
							((iBoxNewRotate = RANDOM % ${countBox[$iBoxNewType]}))
							for ((j = 0, i = (${offsetBox[$iBoxNewType]} + $iBoxNewRotate) * 8; j < 8; j++, i++))
							    do
								boxNew[$j]=${box[$i]};
							    done

								((cBoxNew = ${colorTable[RANDOM % ${#colorTable[@]}]}))

#显示右边预显示的方块
								echo -ne "\033[1m\033[7m\033[3${cBoxNew}m\033[4${cBoxNew}m"
								for ((j = 0; j < 8; j += 2))
								    do
									((i = iTop + 1 + ${boxNew[$j]}))
									    ((t = iLeft + 2 * iTrayWidth + 7 + 2 * ${boxNew[$j + 1]}))
									    echo -ne "\033[${i};${t}H[]"
									    done
									    echo -ne "\033[0m"
}


#初始绘制
function InitDraw()
{
    clear
	RandomBox        #随机产生方块，这时右边预显示窗口中有方快了
	RandomBox        #再随机产生方块，右边预显示窗口中的方块被更新，原先的方块将开始下落
	local i t1 t2 t3

#显示边框
	echo -ne "\033[1m"
	echo -ne "\033[3${cBorder}m\033[4${cBorder}m"

	((t2 = iLeft + 1))
	((t3 = iLeft + iTrayWidth * 2 + 3))
	for ((i = 0; i < iTrayHeight; i++))
	    do
		((t1 = i + iTop + 2))
		    echo -ne "\033[${t1};${t2}H||"
		    echo -ne "\033[${t1};${t3}H||"
		    done

		    ((t2 = iTop + iTrayHeight + 2))
		    for ((i = 0; i < iTrayWidth + 2; i++))
			do
			    ((t1 = i * 2 + iLeft + 1))
				echo -ne "\033[${iTrayTop};${t1}H=="
				echo -ne "\033[${t2};${t1}H=="
				done
				echo -ne "\033[0m"


#显示"Score"和"Level"字样
				echo -ne "\033[1m"
				((t1 = iLeft + iTrayWidth * 2 + 7))
				((t2 = iTop + 10))
				echo -ne "\033[3${cScore}m\033[${t2};${t1}HScore"
				((t2 = iTop + 11))
				echo -ne "\033[3${cScoreValue}m\033[${t2};${t1}H${iScore}"
				((t2 = iTop + 13))
				echo -ne "\033[3${cScore}m\033[${t2};${t1}HLevel"
				((t2 = iTop + 14))
				echo -ne "\033[3${cScoreValue}m\033[${t2};${t1}H${iLevel}"
				echo -ne "\033[0m"
}


#退出时显示GameOVer!
function ShowExit()
{
    local y
	((y = iTrayHeight + iTrayTop + 3))
	echo -e "\033[${y};0HGameOver!\033[0m"
	exit
}


#显示用法.

#游戏主程序在这儿开始.
if [[ "$1" == "-h" || "$1" == "--help" ]]; then
Usage
elif [[ "$1" == "--version" ]]; then
echo "$APP_NAME $APP_VERSION"
elif [[ "$1" == "--show" ]]; then
#当发现具有参数--show时，运行显示函数
RunAsDisplayer
else
bash $0 --show&        #以参数--show将本程序再运行一遍
RunAsKeyReceiver $!        #以上一行产生的进程的进程号作为参数
fi
